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1 - Any suggestions for a "good" ad blocker? IIRC, I installed ad blockers on both Safari and FF.
2 - Will pass along MalwareBytes tomorrow. Thanks. You're right, click-bait-clickers sure are needless risk takers; but try as I may, they can't seem to resist-- it's like they're poster children for people that can't help but respond to click bait, because they truly can't figure out it's click bait.
3 - Don't recall which "internet security" software was used, but IIRC, it was a pseudo legacy from his prior iMac that was updated/reinstalled after I helped set up his new iMac. Old iMac ran SL, and I set new iMac up w/ Mavs and put SL Server on VMWare Fusion as a repository for decades of POP email archives. User had security software reinstalled remotely by vendor, and also did Yos upgrade when I wasn't around. I did a Yos combo updater afterwards when he had "issues", but this Yahoo behavior is quite recent in FF, so I'm thinking something had to have changed; whether some new click bait was clicked, or a setting/ pref got tweaked, or a bug/issue incompatibility w/ something that was updated.
FWIW, husband uses FF and has his account settings saved for a bunch of corporate websites, and add'l native language usage, and wife uses Safari for her stuff; some at same corp websites and different native language. They do use each others' browsers for just general surfing, but use their own to log onto sites that require logins. A lot of family related emails come mostly to husband, so he either forwards stuff to her, or puts a copy in separate "wife" folder in email reader.
I'm gonna try to assist him by phone tomorrow afternoon, so trying to round up possible solutions to tide him over for at least a couple more weeks until I can make a house call. Thanks.
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